CAPE CANAVERAL, Fla. (AP) — A NASA spacecraft rammed an asteroid at blistering speed Monday in an unprecedented dress rehearsal for the day a killer rock menaces Earth.
The galactic grand slam occurred at a harmless asteroid 7 million miles (9.6 million kilometers) away, with the spacecraft named Dart plowing into the small space rock at 14,000 mph (22,500 kph). Scientists expected the impact to carve out a crater, hurl streams of rocks and dirt into space and, most importantly, alter the asteroid’s orbit.
Telescopes around the world and in space aimed at the same point in the sky to capture the spectacle. Though the impact was immediately obvious — Dart’s radio signal abruptly ceased — it will be days or even weeks to determine how much the asteroid’s path was changed.
The $325 million mission was the first attempt to shift the position of an asteroid or any other natural object in space.
“No, this is not a movie plot,” NASA Administrator Bill Nelson tweeted earlier in the day. ”We’ve all seen it on movies like ‘Armageddon,’ but the real-life stakes are high,” he said in a prerecorded video.
Monday’s target: a 525-foot (160-meter) asteroid named Dimorphos. It’s actually a moonlet of Didymos, Greek for twin, a fast-spinning asteroid five times bigger that flung off the material that formed the junior partner.
The pair have been orbiting the sun for eons without threatening Earth, making them ideal save-the-world test candidates.
Launched last November, the vending machine-size Dart — short for Double Asteroid Redirection Test — navigated to its target using new technology developed by Johns Hopkins University’s Applied Physics Laboratory, the spacecraft builder and mission manager.
Dart’s on-board camera, a key part of this smart navigation system, caught sight of Dimorphos barely an hour before impact.
“Woo hoo,” exclaimed Johns Hopkins mission systems engineer Elena Adams. "We’re seeing Dimorphos, so wonderful, wonderful.”
With an image beaming back to Earth every second, Adams and other ground controllers in Laurel, Maryland, watched with growing excitement as Dimorphos loomed larger and larger in the field of view alongside its bigger companion.
A mini satellite followed a few minutes behind to take photos of the impact. The Italian Cubesat was released from Dart two weeks ago.
Scientists insisted Dart would not shatter Dimorphos. The spacecraft packed a scant 1,260 pounds (570 kilograms), compared with the asteroid’s 11 billion pounds (5 billion kilograms). But that should be plenty to shrink its 11-hour, 55-minute orbit around Didymos.
The impact should pare 10 minutes off that, but telescopes will need anywhere from a few days to nearly a month to verify the new orbit. The anticipated orbital shift of 1% might not sound like much, scientists noted. But they stressed it would amount to a significant change over years.
Planetary defense experts prefer nudging a threatening asteroid or comet out of the way, given enough lead time, rather than blowing it up and creating multiple pieces that could rain down on Earth. Multiple impactors might be needed for big space rocks or a combination of impactors and so-called gravity tractors, not-yet-invented devices that would use their own gravity to pull an asteroid into a safer orbit.
“The dinosaurs didn’t have a space program to help them know what was coming, but we do,” NASA’s senior climate adviser Katherine Calvin said, referring to the mass extinction 66 million years ago believed to have been caused by a major asteroid impact, volcanic eruptions or both.
The non-profit B612 Foundation, dedicated to protecting Earth from asteroid strikes, has been pushing for impact tests like Dart since its founding by astronauts and physicists 20 years ago. Monday’s feat aside, the world must do a better job of identifying the countless space rocks lurking out there, warned the foundation’s executive director, Ed Lu, a former astronaut.
Significantly less than half of the estimated 25,000 near-Earth objects in the deadly 460-foot (140-meter) range have been discovered, according to NASA. And fewer than 1% of the millions of smaller asteroids, capable of widespread injuries, are known.
The Vera Rubin Observatory, nearing completion in Chile by the National Science Foundation and U.S. Energy Department, promises to revolutionize the field of asteroid discovery, Lu noted.
Finding and tracking asteroids, “That’s still the name of the game here. That’s the thing that has to happen in order to protect the Earth,” he said.
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CAPE CANAVERAL, Fla. (AP) — In the first-of-its kind, save-the-world experiment, NASA is about to clobber a small, harmless asteroid millions of miles away. Click here to watch
A spacecraft named Dart will zero in on the asteroid Monday, intent on slamming it head-on at 14,000 mph (22,500 kph). The impact should be just enough to nudge the asteroid into a slightly tighter orbit around its companion space rock — demonstrating that if a killer asteroid ever heads our way, we’d stand a fighting chance of diverting it.
“This is stuff of science-fiction books and really corny episodes of “StarTrek” from when I was a kid, and now it's real,” NASA program scientist Tom Statler said Thursday.
Cameras and telescopes will watch the crash, but it will take days or even weeks to find out if it actually changed the orbit.
The $325 million planetary defense test began with Dart’s launch last fall.
ASTEROID TARGET
The asteroid with the bull’s-eye on it is Dimorphos, about 7 million miles (9.6 million kilometers) from Earth. It is actually the puny sidekick of a 2,500-foot (780-meter) asteroid named Didymos, Greek for twin. Discovered in 1996, Didymos is spinning so fast that scientists believe it flung off material that eventually formed a moonlet. Dimorphos — roughly 525 feet (160 meters) across — orbits its parent body at a distance of less than a mile (1.2 kilometers).
“This really is about asteroid deflection, not disruption," said Nancy Chabot, a planetary scientist and mission team leader at Johns Hopkins University's Applied Physics Laboratory, which is managing the effort. "This isn’t going to blow up the asteroid. It isn’t going to put it into lots of pieces.” Rather, the impact will dig out a crater tens of yards (meters) in size and hurl some 2 million pounds (1 million kilograms) of rocks and dirt into space.
NASA insists there’s a zero chance either asteroid will threaten Earth — now or in the future. That’s why the pair was picked.
DART, THE IMPACTOR
The Johns Hopkins lab took a minimalist approach in developing Dart — short for Double Asteroid Redirection Test — given that it’s essentially a battering ram and faces sure destruction. It has a single instrument: a camera used for navigating, targeting and chronicling the final action. Believed to be essentially a rubble pile, Dimorphos will emerge as a point of light an hour before impact, looming larger and larger in the camera images beamed back to Earth. Managers are confident Dart won’t smash into the larger Didymos by mistake. The spacecraft’s navigation is designed to distinguish between the two asteroids and, in the final 50 minutes, target the smaller one.
The size of a small vending machine at 1,260 pounds (570 kilograms), the spacecraft will slam into roughly 11 billion pounds (5 billion kilograms) of asteroid. “Sometimes we describe it as running a golf cart into a Great Pyramid,” said Chabot.
Unless Dart misses — NASA puts the odds of that happening at less than 10% — it will be the end of the road for Dart. If it goes screaming past both space rocks, it will encounter them again in a couple years for Take 2.
SAVING EARTH
Little Dimorphos completes a lap around big Didymos every 11 hours and 55 minutes. The impact by Dart should shave about 10 minutes off that. Although the strike itself should be immediately apparent, it could take a few weeks or more to verify the moonlet’s tweaked orbit. Cameras on Dart and a mini tagalong satellite will capture the collision up close. Telescopes on all seven continents, along with the Hubble and Webb space telescopes and NASA’s asteroid-hunting Lucy spacecraft, may see a bright flash as Dart smacks Dimorphos and sends streams of rock and dirt cascading into space. The observatories will track the pair of asteroids as they circle the sun, to see if Dart altered Dimorphos’ orbit. In 2024, a European spacecraft named Hera will retrace Dart’s journey to measure the impact results.
Although the intended nudge should change the moonlet’s position only slightly, that will add up to a major shift over time, according to Chabot. "So if you were going to do this for planetary defense, you would do it five, 10, 15, 20 years in advance in order for this technique to work,” she said. Even if Dart misses, the experiment still will provide valuable insight, said NASA program executive Andrea Riley. “This is why we test. We want to do it now rather than when there’s an actual need,” she said.
ASTEROID MISSIONS GALORE
Planet Earth is on an asteroid-chasing roll. NASA has close to a pound (450 grams) of rubble collected from asteroid Bennu headed to Earth. The stash should arrive next September. Japan was the first to retrieve asteroid samples, accomplishing the feat twice. China hopes to follow suit with a mission launching in 2025. NASA’s Lucy spacecraft, meanwhile, is headed to asteroids near Jupiter, after launching last year. Another spacecraft, Near-Earth Asteroid Scout, is loaded into NASA’s new moon rocket awaiting liftoff; it will use a solar sail to fly past a space rock that’s less than 60 feet (18 meters) next year. In the next few years, NASA also plans to launch a census-taking telescope to identify hard-to-find asteroids that could pose risks. One asteroid mission is grounded while an independent review board weighs its future. NASA’s Psyche spacecraft should have launched this year to a metal-rich asteroid between Mars and Jupiter, but the team couldn’t test the flight software in time.
HOLLYWOOD’S TAKE
Hollywood has churned out dozens of killer-space-rock movies over the decades, including 1998′s “Armageddon” which brought Bruce Willis to Cape Canaveral for filming, and last year's “Don’t Look Up” with Leonardo DiCaprio leading an all-star cast. NASA’s planetary defense officer, Lindley Johnson, figures he’s seen them all since 1979′s “Meteor,” his personal favorite “since Sean Connery played me.” While some of the sci-fi films are more accurate than others, he noted, entertainment always wins out. The good news is that the coast seems clear for the next century, with no known threats. Otherwise, “it would be like the movies, right?” said NASA’s science mission chief Thomas Zurbuchen. What’s worrisome, though, are the unknown threats. Fewer than half of the 460-foot (140-meter) objects have been confirmed, with millions of smaller but still-dangerous objects zooming around. “These threats are real, and what makes this time special, is we can do something about it,” Zurbuchen said. Not by blowing up an asteroid as Willis’ character did — that would be a last, last-minute resort — or by begging government leaders to take action as DiCaprio’s character did in vain. If time allows, the best tactic could be to nudge the menacing asteroid out of our way, like Dart.
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